As I mentioned above (section REF ) it is not clear at all that the merger process leaves any helium from the core. In the core-WD merger process either the WD or the core stay intact, and the other object is tidally destroyed. The helium, being on the outer part of the core, is mixed with the CO of the destroyed object, being the WD or the core. Therefore, if the process leaves any helium, the helium is mixed with the carbon and oxygen in the outer parts of the merger remnants. At the outer regions the densities are too low for the pycnonuclear reactions that [1]} studied to take place. [1]} proposed an isolated sub-Chandrasekhar WD scenario for SNe Ia. In their scenario pycnonuclear reactions between carbon and tiny amounts of hydrogen or helium during the crystallisation of the WD ignite a SN Ia explosion.
